Polyphasic Characterization of Lysobacter maris sp. nov., a Bacterium Isolated from Seawater

Luteimonas flava sp. nov. and Aquilutibacter rugosus gen. nov., sp. nov., isolated from freshwater environments in China and re-examining the taxonomic status of genera Luteimonas and Lysobacter

Three Gram-stain-negative, aerobic, short rod-shaped and motile strains (FXH3WT, SHGZ20W and SMYT11WT) were isolated from freshwater environments in China. Comparisons based on the 16S rRNA gene sequences indicated that strains FXH3WT and SHGZ20W showed the highest 16S rRNA gene sequence similarity of about 99.6% to 'Luteimonas cellulosilyticus' MIC 1.5, and strain SMYT11WT showed the highest 16S rRNA gene sequence similarity of 99.8% to Luteimonas fraxinea D4P002T, respectively. Observing the phylogenetic trees reconstructed based on the 16S rRNA gene sequences, the species of genera Luteimonas and Lysobacter were not monophyletic and often mixed together. The further reconstructed phylogenomic tree and Genome Taxonomy Database also showed that the species of both genera were polyphyletic, implying that the current taxonomic status of the species of both genera was questionable. The calculated OrthoANIu, digital DNA-DNA hybridization and average amino acid sequence identity (AAI) values supported that strains FXH3WT and SHGZ20W should belong to the same novel species and strain SMYT11WT should also represent an independent novel species. Combining the AAI values and phylogenomic analyses, the species of genera Luteimonas and Lysobacter should be reassigned to 12 genera (Luteimonas, Lysobacter, Cognatiluteimonas, Noviluteimonas, Pseudoluteimonas, Solilutibacter, Agrilutibacter, Cognatilysobacter, Marilutibacter, Novilysobacter, Montanilutibacter and Aerolutibacter). The AAI values 69.5-76.0% were also proposed as the Lysobacteraceae-specific thresholds for genus delineation. Strain SMYT11WT should represent a novel species of the genus Luteimonas, for which the name Luteimonas flava sp. nov. (type strains SMYT11WT=GDMCC 1.4275T=KCTC 8304T) is proposed. Strains FXH3WT and SHGZ20W should represent a novel species of a new genus Aquilutibacter rugosus gen. nov., sp. nov. The type strain of the type species is FXH3WT (=GDMCC 1.4096T=KCTC 8154T).

Parvicella tangerina gen. nov., sp. nov. (Parvicellaceae fam. nov., Flavobacteriales), first cultured representative of the marine clade UBA10066, and Lysobacter luteus sp. nov., from activated sludge of a seawater-processing wastewater treatment plant

Two strains isolated from a sample of activated sludge that was obtained from a seawater-based wastewater treatment plant on the southeastern Mediterranean coast of Spain have been characterized to achieve their taxonomic classification, since preliminary data suggested they could represent novel taxa. Given the uniqueness of this habitat, as this sort of plants are rare in the world and this one used seawater to process an influent containing intermediate products from amoxicillin synthesis, we also explored their ecology and the annotations of their genomic sequences. Analysis of their 16S rRNA gene sequences revealed that one of them, which was orange-pigmented, was distantly related to Vicingus serpentipes (family Vicingaceae ) and to other representatives of neighbouring families in the order Flavobacteriales (class Flavobacteriia ) by 88–89 % similarities; while the other strain, which was yellow-pigmented, was a putative new species of Lysobacter (family Xanthomonadaceae , order Xanthomonadales , class Gammaproteobacteria ) with Lysobacter arseniciresistens as closest relative (97.3 % 16S rRNA sequence similarity to its type strain). Following a polyphasic taxonomic approach, including a genome-based phylogenetic analysis and a thorough phenotypic characterization, we propose the following novel taxa: Parvicella tangerina gen. nov., sp. nov. (whose type strain is AS29M-1T=CECT 30217T=LMG 32344T), Parvicellaceae fam. nov. (whose type genus is Parvicella), and Lysobacter luteus sp. nov. (whose type strain is AS29MT=CECT 30171T=LMG 32343T).

Lysobacter antarcticus sp. nov., an SUF-system-containing bacterium from Antarctic coastal sediment

A Gram-stain-negative, heterotrophic, aerobic, non-motile, rod-shaped bacterial strain (GW1-59T) belonging to the genus Lysobacter was isolated from coastal sediment collected from the Chinese Great Wall Station, Antarctica. The strain was identified using a polyphasic taxonomic approach. The strain grew well on Reasoner's 2A media and could grow in the presence of 0–4 % (w/v) NaCl (optimum, 1 %), at pH 9.0–11.0 and at 15–37 °C (optimum, 30 °C). Strain GW1-59T possessed ubiquinone-8 as the sole respiratory quinone. The major phospholipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids were summed feature 9 (10-methyl C16 : 0 and/or iso-C17 : 1  ω9c), iso-C15 : 0, iso-C16 : 0, iso-C17 : 0, C16 : 0 and iso-C11 : 0 3-OH. DNA–DNA relatedness with Lysobacter concretionis Ko07T, the nearest phylogenetic relative (98.5 % 16S rRNA gene sequence similarity) was 23.4 % (21.1–25.9 %). The average nucleotide identity value between strain GW1-59T and L. concretionis Ko07T was 80.1 %. The physiological and biochemical results and low level of DNA–DNA relatedness suggested the phenotypic and genotypic differentiation of strain GW1-59T from other Lysobacter species. On the basis of phenotypic, phylogenetic and genotypic data, a novel species, Lysobacter antarcticus sp. nov., is proposed. The type strain is GW1-59T (=CCTCC AB 2019390T=KCTC 72831T).

Lysobacter segetis sp. nov., Isolated from Soil

A Gram-negative, aerobic, motile by gliding, rod-shaped bacterium, strain 17J68-2^T, was isolated from a soil sample taken from Jeju Island, Republic of Korea. The isolate displayed high 16S rRNA gene sequence similarity to the members of the genus Lysobacter in the family Lysobacteraceae, with Lysobacter humi FJY8^T (98.4% similarity), Lysobacter xinjiangensis RCML-52^T (98.3%), and Lysobacter mobilis 9NM-14^T (98.1%) as closest phylogenetic neighbors. Growth of strain 17J68-2^T occurred at 15-42 °C, pH 7-8, and in the presence of 0-1.0% NaCl. Draft genome was 2.94 Mb in size with G+C content of 70.5 mol%. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylethanolamine. Ubiquinone Q-8 was the predominant respiratory quinone and the major fatty acids were C_16:0 iso (39.4%), summed feature 3 (C_16:1ω7c/C_16:1ω6c) (6.6%), C_11:0 iso 3-OH (6.4%), C_15:0 iso (6.4%), and C_16:1 iso H (6.2%). The DNA-DNA relatedness between strain 17J68-2^T and L. humi, L. xinjiangensis, and L. mobilis were 39.9, 39.4, and 25.3%, respectively. From these results, it is concluded that the novel isolate possesses sufficient characteristics to differentiate it from the most closely affiliated Lysobacter species, and strain 17J68-2^T represents a novel species of the genus Lysobacter, for which the name Lysobacter segetis sp. nov. (=KCTC 62237^T = JCM 33058^T) is proposed.